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The Western Palaearctic species of the genus Caenaphanes Foerster are reviewed. A new species from the Canary Islands, C. lapalmaensis sp. nov., is described. The name C. rugosifrons (Picard) is restored from synonymy (stat. resurr.). The redescriptions of C. incompletus (Ratzeburg) and C. rugosifrons are given. A key to the Western Palaearctic species of Caenophanes is suggested.
All the west-palearctic species of the genus Phyllobrotica Chevrolat, 1837 are discussed and illustrated. The distributional data and a key for the identification of the known species and of a new species here described are given. A new species Ph. aslani from Turkey is described, the synonymy Ph. humeralis Kraatz 1891 = Ph. frontalis Weise 1886 is proposed.
The monographic revision of North Korean ants is provided fist time in the World literature. This work was based on the investigation of very rich material collected by Polish and Hungarian entomologists in North Korea in 1959-1990. The collections are kept in the Museum and Institute of Zoology of the Polish Academy of Sciences, Warsaw, in the Institute of Environmental Sciences of the Jagiellonian University, Cracow, and in the Hungarian Natural History Museum, Budapest. In total, these unique collections include more than 70 thousand specimens collected in almost all regions of North Korea. Altogether, 99 ant species from 35 genera and 7 subfamilies, including 6 newly described species and 35 new to North Korea have been found; 17 species have been excluded from the list of the North Korean fauna. The monograph includes review of species, taxonomie and zoogeographical analysis of the Korean myrmecofauna, and the comparison of this fauna with that of the adjacent regions of Eastern Asia. A key for determination of all taxa of North Korean ants is also provided.
We have synthesized the data on population dynamics and densities of rodents in seven biomes of the Palearctic (mainly western part), and related them to the data on standing crop of biomass and net productivity of ground vegetation (as rough indicators of food availability to rodents). Analysis of 44 long-term (> 5 years) series of rodent trapping showed that there was a continuum from highly cyclic to non-cyclic populations. Rodents inhabiting tundra, taiga, steppe, and farmlands (wintercrops) in the temperate zone have highest cyclicity indices. Definitely non-cyclic are rodents in the temperate forests (mixed and deciduous forests, steppe woodland) and desert. Standing crop of biomass of ground vegetation (analysis of 63 data points) correlated positively with latitude; it was highest in the northern tundra and decreased towards South. Variation within biomes was most pronounced in the temperate zone, with forests having ground vegetation biomass as low as that in deserts, whereas farmlands in that zone — as high as that in tundra. In various habitats (natural open, farmland, and forested) located in seven biomes, the mean index of rodent cyclicity was significantly positively correlated to the mean standing crop of ground vegetation. Net productivity of ground vegetation (30 data points) did not show latitudinal trends. It was lowest in desert, tundra, and all types of forests, and highest in open habitats of the temperate zone and steppes. Mean densities of rodents (calculated as averaged spring and autumn estimates) were lowest in tundra, desert, and all types of forests (8—29 rodents/ha). The highest average densities were recorded in the farmlands of temperate zone and steppe (143-490 rodents/ha), Mean and maximum densities of rodents were strongly positively correlated with the mean productivity of ground vegetation. Dichotomy between seasonal (non-cyclic) and multiannual (cyclic) fluctuations in rodent numbers was not found. The magnitude of seasonal changes in rodent densities (from spring to autumn) was a continuous variable related to the propitiousness of climate for plant growth. Irrespectively of the type of population dynamics, seasonal changes in rodent densities were small in the coolest and the hottest biomes (tundra, desert) and big in the temperate zone. Results of our long-term study on predation on rodents in the temperate deciduous forests did not support the hypothesis on the role of specialist and generalist predators in shaping rodent dynamics. We found no qualitative difference between predatory impacts by generalist and specialist predators. All predators exerted the heaviest impact at low or moderate densities of rodents (inversely density-dependent predation). Predation may be an important factor of rodent mortality but it does not shape the pattern of rodent population dynamics. Based on the observed vegetation-rodent correlations, we have proposed an inter­pretation of the mechanisms of rodent population dynamics in the Palearctic biomes. A prerequisite for rodent cycles to occur is abundant winter food, which enables rodents to continue an increase phase beyond one growing season (by winter breeding). Habitats with mean standing crop of ground vegetation of over 4000 kg dry weight/ha in summer are expected to harbour cyclic populations of rodents.
The two European species of vertebrate blood-feeding biting midges of the subgenus Lasiohelea Kieffer, 1921 of the genus Forcipomyia Meigen, 1918 are taxonomically reviewed. They are Forcipomyia (Lasiohelea) velox (Winnertz, 1852), whose adult females feed on amphibians, and F. (L.) sibirica (Buyanova, 1962), which obtain blood from humans. Adults of both species are diagnosed, redescribed and illustrated. Forcipomyia sibirica is a boreo-montane Palearctic species which, in Europe, mostly occurs in mountain areas, and is very similar to the eastern Palearctic F. (L.) nipponica (Tokunaga, 1940). Forcipomyia velox is common in western Palearctic lowlands. Forcipomyia (L.) cultella (Yu et Xiang, in Yu 1988) from China is recognized as a junior synonym of F. velox (Winnertz, 1852), and F. (L.) ussurica Remm, 1971 from the Russian Far East is recognized as a junior synonym of F. (L.) longicornis (Tokunaga, 1940) from Japan. New synonymies. Forcipomyia sibirica from Romania and F. longicornis from North Korea are reported for the first time.
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